1. Field of the Invention
The present invention relates notably to an information or data encoding method. It relates, for example, to transmission security in networks. It applies, for example, in wired and wireless transmission networks.
2. Prior Art
In wireless networks, the constraints are high, there is often a low computation capacity, transmission problems (noise-affected channels) and weak flows. One of the problems encountered is how to protect the transmitted information, that is to say, how to find a solution that makes it possible to observe the anonymity of the users wishing to exchange information and guarantee that this information cannot be accessed by malicious hackers, while retaining good traffic quality, that is to say, without adding too much latency. In practical terms, it is easy for a hacker to intercept any communication in a given region, when in a wireless environment. The standard encryption systems with public keys that can be used to encrypt the address of the node of a communication network are generally very slow compared to the needs of the application. A number of solutions that use private key encryption systems are known from the prior art. These solutions do not, however, offer high security, because each node of the network must know the private key of the others. This means that, when a node is corrupted, the security of the network collapses.
The document by William Luh, Deepa Kundur, entitled “Distributed Privacy for Visual Sensor Networks via Markov Shares” In Proceedings of the Second IEEE Workshop on Dependability and Security in Sensor Networks and Systems, 2006, discloses a method that divides up the information before transmitting it. This solution protects the information only if it is assumed that the hacker is capable of intercepting only a small fraction of the information. This assumption is improbable in a wireless context. Another drawback of the method described is that it does not guarantee the anonymity of the users. The document by V. M. Sidel'nikov, entitled “A public-key cryptosystem based on Reed-Muller codes” Discrete Mathematics and Applications, 4(3):191-207, 1994, also describes a public key encryption system that uses the property of the Muller codes and retains the principle of adding a random error of fixed weight. The performance of such an algorithm is still weak when considering real-time or almost real-time applications. This article discloses an algorithm that is more restrictive. The length of the key is always important and the complexity of encryption of a message is more important if a high security is to be maintained. The public key encryption system described is probabilistic. There is therefore a non-zero probability that the recipient of the message will not succeed in decrypting the message.
Currently, the systems described in the prior art do not adequately resolve the problems of security when transmitting information in a transmission network and they do not address the problem of the anonymity of the sender and of the receiver.